Celestion FTX1225

• Sensitivity (1W, 1m, infinite baffle) SPL1W 94.2dB
• Frequency response 50 - 20000Hz

Thiele & Small parameters

• Resonance frequency (free air) fS 47.3Hz
• Mechanical quality factor QMS 4.21
• Electrical quality factor QES 0.44
• Total quality factor QTS 0.40

Large signal parameters

• Maximum linear excursion xmax 6mm
• Air volume displaced at xmax VD 319cm³
• Power handling P 300W
• Program power Pmax 600W

Voice Coil

• Nominal impedance Z 8Ω
• DC resistance RE 5.4Ω
• Inductance (1kHz) LE 3.36mH
• VC Diameter 64mm
• Winding height HVC 16mm
• Winding material Edgewound copper clad aluminium
• Former material Glass fibre

Magnet

• Force factor Bl 14N/A
• Motor constant Bl/√RE 6.03N/√W
• Air gap height HAG 8mm
• Weight 2.3kg
• Material Ferrite

Diaphragm

• Effective diameter 260mm
• Effective area SD 531cm²
• Moving mass MMS 53.5g
• Moving mass (without air load) MMD 44.7g
• Material Kevlar loaded paper

Suspensions

• Stiffness KMS 4.72N/mm
• Compliance CMS 212µm/N
• Equivalent volume to the compliance VAS 84.6L
• Mechanical resistance RMS 3.77N·s/m
• Surround material Cloth-sealed

Dimensions

• Nominal diameter 12″
• 305mm
• Overall diameter 318mm
• Baffle cutout diameter 286mm
• Overall depth 168mm
• Volume occupied by the driver (estimated) 3L
• Net weight 5.9kg
• Frame material Cast aluminium